Tag: anesthesia

How could the study of patients under anesthesia lead to a new way to diagnose Alzheimer’s disease? It could all come down to brainwaves.

Patrick Purdon, PhD, a researcher with the Massachusetts General Hospital Department of Anesthesia, Critical Care and Pain Medicine, is investigating how changes in brainwave patterns could potentially detect early signs of Alzheimer’s disease.

For the past decade, Purdon and his colleagues have been using electroencephalogram, called EEG, to measure the brainwaves of patients under sedation. That research has demonstrated that different anesthetic drugs produce distinct brainwave patterns in patients. After finding these brainwave patterns in elderly patients under anesthesia were slower and smaller than those of younger adult patients, Purdon and colleagues examined the areas that were affected by age and discovered they align with brain areas that typically undergo degeneration in Alzheimer’s.

This led to an intriguing possibility—could EEG measurements be used as a diagnostic tool for Alzheimer’s disease?

With a grant from the NIH, Purdon is now studying the brainwave patterns of early Alzheimer’s patients, and monitoring how those brainwaves change over the progression of the disease. Purdon and his team hope to determine whether EEG can provide a clearer picture of the process of neurodegeneration and changes in brain function.

If they’re successful, EEG could be used as an inexpensive alternative for screening of neurodegenerative problems, potentially leading to earlier diagnosis of Alzheimer’s disease, where treatments could be more effective at slowing or halting its progression. Brainwave measurements could also provide a more accurate measure of the disease’s progression over time.

Emery Brown, MD, PhD, and a team of collaborating investigators from Massachusetts General Hospital are hoping to make a fundamental change in the way anesthesiologists think about the process of sedation—one that changes the focus from the body to the brain.

“On October 16, 1846, at Massachusetts General Hospital, [William T.G. Morton] successfully administered ether to a surgical patient in a public demonstration. As acclaim was heaped upon Morton, [Horace] Wells unsurprisingly cried foul—but so did [Charles T.] Jackson. A bitter dispute rose all the way to Congress…”

“We know even less about how anesthetic drugs influence brain activity in children, and the current standard of care for assessing the brain state of children under anesthesia calls only for monitoring vital signs like heart rate and blood pressure. This lack of knowledge is
especially troubling, given recent studies suggesting an association between early childhood surgery requiring general anesthesia and later cognitive problems.”